An electrical connection of a semiconductor switching device to an external circuit unit can be important, for example, if the semiconductor switching device has to handle large currents and voltages. An example of such a semiconductor switching device is an integrated gate commutated thyristor (IGCT). An IGCT is a gate-controlled turn-off switch which can turn off like an insulated gate bipolar transistor (IGBT) but conducts like a thyristor with low conductor losses. An integrated gate commutated thyristor is a power switching device for demanding high power applications such as, for example medium voltage drives, traction, wind power converters, AC excitation systems, battery energy storage systems, solid state breakers, traction line boosters, traction power compensators and induction heating. A semiconductor switching device constructed as an IGCT can be used in a variety of applications due to its versatility, efficiency and cost-effectiveness. A known IGCT device can have a ring-shaped structure, as shown in FIG. 1. A cathode disc CD is the lower surface in FIG. 1. On the cathode disc CD, a gate disc GD can be arranged providing a gate connection to the semiconductor device. An anode phase A is arranged on top of a housing H having a creepage distance Cr at the outside.
FIG. 2 is a cross-section of the arrangement shown in FIG. 1. The creepage distance Cr is formed between the anode A and the cathode disc CD. The creeping distance Cr is part of the housing H which can be formed from an insulating material, for example ceramics. In order to connect the cathode disc CD and the gate disc GD to external circuit units, a cathode conductor C and a gate conductor G can be provided. These connections can be performed using two discs, for example the gate disc GD and the cathode disc CD. These discs can be soldered to package ceramics. For mechanical reasons, the thickness of the ceramic which separates the gate disc from the cathode disc should be higher that what would be required to insulate the two potentials which are separated by a voltage of approximately 100 V.
This can result in a large distance between the gate electrode and the cathode electrode such that a total loop inductance is increased. An example of an inductance loop formed in the known connection arrangement for connecting the semiconductor switching device to an external circuit unit is shown by a reference numeral IL in FIG. 2. Stray inductance IL, shown in FIG. 2, deteriorates a turn-off performance of the semiconductor switching device. Also, the size of the semiconductor switching device is large because the thickness of a ceramic housing which separates gate and cathode discs is high.